Project Summary/Abstract The goal of this R01 application is to examine time trends for incident fall injuries in Medicare, including non- fracture fall injuries (NFFI) and fractures, across 20 years of cohort data and if changes in risk factors explains trends, and then to evaluate major geriatric outcomes subsequent to incident NFFI. Unlike osteoporotic fracture, NFFI - defined as fall injuries without fracture - are not treated as hallmarks of geriatric decline, particularly if the presenting injury is not severe (e.g., soft tissue injury). Our preliminary data found fall mortality in older adults increased substantially over the past several decades, with higher increases for the oldest cohorts. We will evaluate if this trend in fall mortality extends to non-fatal medically treated fall injuries over 20 years in several combined epidemiologic cohorts of older adults with overlapping time periods from 1998-2019. The Specific Aims are: 1) To examine time trends for incident fall injuries in Medicare, including NFFI and fractures, across 20 years of cohort data and if changes in risk factors over the time period explains trends; and 2) To determine if incident NFFI predict future inpatient hospitalizations, increased risk of SNF stays and mortality for up to 5 years after NFFI in women and men. In 4 pooled longitudinal cohorts (61% women, 33% minorities, 36% aged >80 years, 27% obese) with in-person exams of 4,653 men and 7,338 women, incident fall injuries will be identified from 5-10 years of self-reported questions and Medicare Fee for Service (FFS) Parts A and B claims. We hypothesize fall injury incidence will increase over time in the combined cohort of nearly 12,000 women and men, with increases higher at the oldest ages, and that overall fall injury incidence and NFFI incidence increases will be partially explained by risk factors of metabolic (e.g., obesity, diabetes, blood pressure) and neuromuscular function (strength, gait speed, chair stand speed) that we have identified in past work as novel risk factors for NFFI. We hypothesize that an estimated 1,867 incident NFFI will predict future inpatient hospitalizations, increased risk of SNF stays and mortality. Our validated approaches from past projects combine extensive cohort data across 20 years and linked Medicare claims to examine increasing trends in fall injuries, including clinical NFFI, as a significant public health issue in old age.